The potency-ratio of ciprofol and propofol under procedural sedation and anesthesia for outpatient hysteroscopy during cervical dilation: a study using up-and-down sequential allocation method.

Background: Ciprofol(HSK3486) is a novel 2,6-disubstituted phenol derivate, a short-acting intravenous sedative, which has similar efficacy characteristics as propofol with less incidence of side effect. Both ciprofol and propofol are often used in outpatient hysteroscopic surgery for sedation. However, the relative potency of these two drugs has not been fully determined in this context.

Objective: Our study aimed to investigate the potency-ratio of ciprofol and propofol under procedural sedation and anesthesia in restraining reaction of outpatient hysteroscopy dilatation.

Methods: The ED50 (effective dose in 50% of subjects) value for ciprofol and propofol were calculated by Up-and-Down Sequential Allocation Method. 60 healthy patients undergoing daytime hysteroscopy were randomly divided into two groups, which were intravenously injected with ciprofol at an initial dose of 0.4 mg/kg (group C) or propofol at an initial dose of 2 mg/kg (group P) at 2 min after intravenous injection of sufentanil 0.15ug/kg. A successful response is defined as the absence of patient movement in the case of cervical dilation. Conversely, the presence of patient movement is defined as failure. After successful or failed responses, each follow-up patient in the corresponding group was reduced or increased with propofol 0.5 mg/kg or ciprofol 0.1 mg/kg, respectively.

Results: The estimated ED50 value for ciprofol and propofol in restraining reaction of hysteroscopy dilatation was 0.444 mg/kg (95% CI, 0.385-0.503 mg/kg) and 1.985 mg/kg (95% CI, 1.801-2.170 mg/kg), respectively. The incidence of respiratory depression, hypoxemia and injection pain in ciprofol was significantly lower than those in propofol.

Conclusion: The ED50 of ciprofol and propofol in preventing hysteroscopy dilatation reaction was 0.444 mg/kg (95% CI, 0.385-0.503 mg/kg) and 1.985 mg/kg (95% CI, 1.801-2.170 mg/kg) for outpatient hysteroscopy. The potency-ratio of ciprofol and propofol observed in our study was 1.0:4.5(95%CI,1:3.9-1:5.1).

Trial registration: The study was registered at Chinese Clinical Trial Registry http//www.chictr.org.cn/ (Registration date19/11/22 Trial ID ChiCTR2200065954).